Electric switch.



No. 656,870. Patented Aug. 28, I900.

' H. H. W'APPLEB.

ELECTRIC SWITCH.

(Application Med Dec. 8, 11:99.

(No Model.)

wifnesscs m: uonms PETERS co, PNOYOLITNQ. wAsumunm. a, c.

at triers.

REINI'IOLD II. \VAPPLER, OF NEI/V YORK, N. Y., ASSIGNCR TO THE W'APPLER ELECTRIC CONTROLLER COMPANY, OF SAME PLACE.

ELECTRIC SWITCH.

SPECIFICATION forming part of Letters Patent No. 656,870, dated August 28, 1900. Application filegmpeoemher 8. 1899- Serial No. 739.596. (No model.)

To all whom it may concern.-

Be it known that LREINHOLD H.WAPPLER, a citizen of the United States, residing at the city of New York, in the county and State of New York, have invented an Improvement in Electric Switches, of which the following is a specification.

In connection with electrically-operated devices, especially dental and surgical instru- IO ments, difficulties have been experienced in operating the switches. These have usually been of large size and unsatisfactory structure and to operate which required that the switch be heldagainst the action of a spring to complete the circuit, and this was difficult for the hand holding the instrument, as the operators other hand was usually fully employed. This condition was a distinct disadvantage. In my improvement the switch is operated by the thumb or one finger of the hand holding the instrument. The switch consists of a roller or wheel and two spacedapart metallic conductors extending across one face of the roller or wheel. This face of the roller is provided with surfaces formed in parallel planes, whereby one surface is always in contact with one metallic conductor and by turning the roller can be brought into contact with the other conductor to complete 0 the electric circuit, a stop being employed on the roller to limit the movement. If the roller be entirely of metal, theone face is divided into segments of varying sizes in parallel planes, with the smaller segment depressed, 5 and if the roller be of hard rubber or similar insulating material a metal segment is secured to one face of the roller, the said segment being preferably of less diameter than the roller, so that a finger upon the periphery 0 will not touch the metal segment.

In the drawings, Figure 1 is an elevation representing my improvement with the parts in a normal position with the circuit broken. Fig. 2 is a plan of thesame; and Fig. 3 is an 5 elevation similar to Fig. 1, but with the circuit completed. Fig. 4 is an elevation, and Fig. 5 a plan, of a modified form of the invention.

The foundation ct is preferably of hard rubher, or may be of other equally available insulating material.

19 represents the roller, and b the axis of the same.

0 d are metal conductors connected to the foundation, but spaced apart at their adjacent ends, as represented, and from these metal conductors extend electric wires 2 8 or other conductors, according to the uses of the device.

The surface-of the roller b adjacent to the metal conductors 0 cl is divided into segmental surfaces'5 6 in parallel planes and preferably of varying sizes, and in this surface is placed a stop 7. The roller 1) ispreferably pressed against the adjacent surface of the conductors 0d, and for this purpose I prefer the springs 4. 9 in socketsin the foundation (1, of insulating material, the ends of the springs bearing against the surface of the roller and the springs placed at opposite sides of H1670 axis 19.

In the modification shown in Figs. 4 and 5 the roller is preferably a hard-rubber or insulating-material disk b upon the surface of which, adjacent to the metalconductors 0 cl, is placed a metal segment 8, secured to the face. This metal'segment agrees with the segment 6 of the roller b, and while Figs. 1 and 4 of the drawings show the normal position of the roller with reference to the metal conductors when the circuit is broken Fig. 3 shows the position after a partial rotation has been given to the roller to turn the same so as to bring the surface of the segment 6 into metallic contact with both of the metal condoctors c d, so as to complete the electric circuit. This roller is readily moved, or, in other words, given a partial rotation, by a finger or by the thumb of the hand holding the instrument. The said roller turns readily 0 and the circuit is made or broken instantly, and the movement of the same in no way interferes with the holding of the instrument and does not produce any movement of the instrument in the hand as the roller is turned. 5

I have shown a metal conductor e upon the opposite surface of the insulating-material foundation a and wires therefrom for the return-circuit; but this forms no part of my present invention.

I have only shown in the drawings the parts described, as the same may be applied to many dental and surgical instruments, and the attendant parts form no part of the present invention.

I claim as my invention- 1. The combination in an electric switch, with a foundation of insulating material and metal conductors connected thereto and spaced apart, of a rotary circuit-closing metal roller having a raised flat surface normally in contact with the surface of one conductor and which, by a partial rotation of the roller,

shifts the same surface also into simultaneous contact with the other metal conductor to completethecircuit,substantiallyassetforth.

2. In an electric switch, the combination with a foundation of hard rubber or other suitable insulating material and metal conductors in the form of bars connected-thereto and spaced apart at their adjacent ends, of a roller pivoted to the foundation and located between the foundation and the metal conductors with the face thereof adjacent to the metal conductors and formed of segmental surfaces in parallel planes whereby one segmental surface is in contact with one metal conductor in a normal position, and in contact with both metal conductors upon giving a partial rotation to the roller, substantially as and for the purposes set forth.

3. In an electric switch, the combination with a foundation of insulating material and metal conductors in the form of bars connected thereto and spaced apart at their adjacent ends, of a roller pivoted .to thefoundation and occupying a position between the same and the said conductors, the face of the roller next to the conductors having a raised segmental surface, a stop upon the surface of the said roller, and means for pressing the said raised surface of the roller against the metal conductors, whereby in one position the raised segmental face is normally in contact with one metal conductor and may be given a partial rotation to bring the same into contact with both metal conductors, substantially as and for the purposes set forth.

4. The combination in an electric switch with a foundation of insulating material, of

a roller and an axis therefor connecting the roller to the foundation, and upon which the roller is adapted to turn, said roller having a segmental metal surface upon the face thereof, metal conductors narrower than the diameter of the roller and extending across the face thereof with the respective ends spaced apart to one side of the center with one conductor in contact with the segmental surface and the end thereof approximately in line with the straight edge of the segmental surface in a normal condition, a stop upon the surface of the roller to limit the movement thereof, the said segmental surface lying against the surface of one metal conductor in the normal position and against the surface of both metal conductors after a partial rotation has been imparted thereto, substantially as and for the purposes set forth.

5. The combination in an electric switch with a foundation of insulating material and metal conductors connected thereto and spaced apart, of a rotary circuit-closing roller pivotally connected to the said foundation and having its periphery projecting beyond the surface of the insulating-material foundation to be operated by the finger in making and breaking the circuit, substantially in the manner and for the purposes set forth.

6. The combination in an electric switch with a foundation of insulating material and metal conductors connected thereto and spaced apart, of a rotary circuit-closing roller pivotally connected to the said foundation and having a raised segmental surface next to and normally in contact with one metal conductor and having its periphery projecting beyond the surface of the insulating-material foundation to be operated by the finger in making and breaking the circuit, substantially in the manner and for the purposes set forth.

Signed by me this 5th day of December, 1899.

REINHOLD H. \VAPPLER.

WVitnesses:

GEO. T. PINCKNEY, S. T. HAVILAND. 

